Abstract:

A torque-sensing flange, or generally a torque measurement recorder, is
proposed, which has differently embodied measurement recesses or
differently embodied measuring diaphragms on an essentially cylindrical
measuring range. Different measuring ranges can be easily achieved in
this manner.

Claims:

1. A torque-measuring flange with an essentially cylindrical measuring
range, in which measuring recesses are arranged, and with measured value
transducers, which measure stresses and/or deformations in the measuring
range, wherein at least two measuring recesses are varyingly embodied.

2. The torque-measuring flange according to claim 1, wherein at least two
measuring recesses exhibit different depths.

3. The torque-measuring flange according to claim 1, wherein at least two
measuring recesses exhibit a different cross section.

6. The torque-measuring flange according to claim 1, wherein at least one
measuring recess exhibits a recess floor that deviates from the
cylindrical form, preferably a flat recess floor.

7. The torque-measuring flange according to claim 1, wherein at least one
measuring recess exhibits a recess floor with a surface corresponding to
the surface of the cylindrical measuring range, toward which the
measuring recess is oriented.

8. The torque-measuring flange according to claim 1, wherein at least one
measuring recess exhibits a round cross section.

9. The torque-measuring flange according to claim 1, wherein at least one
measuring recess exhibits a rectangular, even square, cross section with
rounded corners.

10. The torque-measuring flange according to claim 1, wherein a measured
value transducer is provided for each measuring recess.

12. The torque-measuring flange according to claim 1, wherein at least one
measuring recess changes proceeding from the recess floor, preferably
expands or narrows.

13. A torque-measuring flange with a measuring range arranged around a
rotational axis, in which measuring diaphragms are arranged, and with
measured value transducers, which measure stresses and/or deformations in
the measuring diaphragms, wherein at least two measuring diaphragms are
varyingly embodied.

14. The torque-measuring flange according to claim 13, wherein at least
two measuring diaphragms exhibit a different thickness.

15. The torque-measuring flange according to claim 13, wherein at least
two measuring diaphragms exhibit a different shape.

26. The torque-measuring flange according to claim 1, wherein at least one
measured value transducer is arranged radially inward on the measuring
range.

27. The torque-measuring flange according to claim 1, wherein at least one
measured value transducer is arranged radially outward on the measuring
range.

Description:

[0001]The invention relates to a torque-measuring flange.

[0002]Measuring constant or dynamic torques is a routine task encountered
in numerous areas of technology. A plurality of known torques-sensing
flanges, also referred to generally as torque measuring transducers,
exists to cover the various applications, installation conditions and
precision requirements.

[0003]DE 199 36 293 depicts a torque-measuring flange, in which an
essentially cylindrical hollow shaft segment is situated between two
annularly circular coupling flanges. This hollow shaft segment makes up
the measuring range of the torque-measuring flange. The essentially
cylindrical wall incorporates three large measurement recesses, thereby
yielding three measuring diaphragms on the cylindrical inner wall. An
introduced torque can give rise to relatively large deformations given
the relatively slight wall thickness of the measuring diaphragm, so that
expansion-measuring strips applied thereto permit the relatively accurate
calculation of the applied torque. For smaller torques, the measuring
diaphragm can be situated radially inward. For larger torques to be
measured, the diaphragm can be situated radially outward. The publication
also proposes that the pocket-shaped recesses be arranged opposite each
other, thereby yielding an H-profile, or that the recesses radially
alternate, so that they alternatingly proceed from the inner followed by
the outer jacket surface of the cylinder form.

[0005]The object of the invention is to provide an improved
torque-measuring flange.

[0006]In a first aspect of the invention, this object is achieved by means
of a torque-measuring flange with an essentially cylindrical measuring
range, in which measuring recesses are situated, and by means of measured
value transducers, which measure stresses and/or deformations in the
measuring range, wherein at least two measuring recesses are shaped
and/or embodied differently.

[0007]With respect to terminology, let it first be explained that the
"measuring range" is regarded as the range of the entire measured value
transducer formed between the two flange-like connection areas, and
non-positively connects them with each other. For example, when a torque
is applied to the two connection areas on a machine or test bench,
meaning in particular to the two flanges, the measuring range is also
subjected to that torque. The measuring range is usually circularly,
annularly circular or at least essentially circular or annularly circular
in cross section, perpendicular to the axis around which the torque is
acting. Annularly circularly cross sections are most often encountered.

[0009]The introduced aspect of the invention is characterized in that it
forms and/or embodies two such measuring recesses differently. These can
be both radially inward recesses with a different shaped, and radially
outward recesses, if radially inward and radially outward recesses are
present in the measuring range. In particular, however, let it be
imagined that radially outward recesses of varying shape are visible
inside the family of radially inward recesses and/or inside the family of
radially outward recesses.

[0010]As a result of the various shapes of the recesses, a torque applied
to the measuring points of the individual, different measuring recesses
triggers varying deformations and/or stresses, thereby making it
possible, for example, for a single torque measuring-flange to enable
several more highly resolved or several varyingly resolved measuring
ranges.

[0011]It is preferred for at least two measuring recesses exhibit
different depths. Providing different measuring recesses with varying
depths, in particular within a family of radially inward and/or a family
of radially outward measuring recesses, generates varying expansions and
stresses in the remaining floors radially outward or radially inward of
the recesses, meaning in the measuring diaphragms, given a suitable
design.

[0012]Two measuring recesses preferably exhibit a different cross section.
With respect to terminology, let it first be explained that the "cross
section" of a recess is to be understood in particular as the surface
that forms in a cutting plane perpendicular to the axis of the
torque-measuring flange between the material limits of the recesses and a
circular, smallest peripheral as the free surface. Specifically, a cut
perpendicular to the axis of the torque-measuring flange will yield a
cutting geometry at a measuring recess that has at least two lateral
edges from ed by the at least essentially massive cylinder wall, and that
might exhibit a floor radially inward or radially outward, i.e.,
basically a measuring diaphragm, wherein the lateral edges can run
radially in the simplest case. The remaining free surface of the recess
within these limits and a circular peripheral outside and/or inside on
the cylindrical measuring range would then be regarded as the cross
section of the measuring recess.

[0013]As an alternative, the "cross section" can be taken as the resultant
free surface that arises given a cut with a plane parallel to the axis of
the torque-measuring flange, or the "cross section" can be taken as the
resultant free surface that arises given a cut with a cylindrical jacket
surface around the axis of the torque-measuring flange during its
development.

[0014]If two measuring recesses exhibit a different cross section, an
applied torque triggers a varying expansion and/or stress distribution,
at least at one edge area of the recess, so that measurements can here
also be readily performed for measuring areas resolved to varying
degrees.

[0015]At least essentially uniformly embodied measuring recesses are
preferably arranged symmetrically relative to a rotational axis of the
torque flange, in particular rotationally symmetrically. Given a suitable
design, the same tension and/or expansion behavior can as a result be
expected at the measuring points on a family of identical or identically
embodied measuring recesses, especially if all measuring recesses at the
torque-measuring flange belong to a respective family of identical and
symmetrically distributed recesses.

[0017]With respect to terminology, the above will be explained as follows:
The torque-measuring flange has a longitudinal axis, around which the
applied torques are to be measured. An outer cylindrical jacket surface
around this axis can be imagined, which represents the smallest
peripheral of the at least essentially cylindrical measuring range. As a
rule, the measuring range will be designed cylindrical radially outward,
so that the cylinder jacket surface of the cylindrical measuring range
precisely corresponds to its radially outward surface. Radially outward
measuring recesses extend radially inward from the cylinder jacket
surface, wherein each measuring recess has a recess wall and recess
floor, although the latter can converge without any clear seam. A
"partially cylindrical recess floor" is on hand when the measuring recess
at least partially exhibits a surface that is spatially bent in such a
way as to represent a part of an imagined cylinder jacket surface.
Possibilities include in particular an imagined cylinder, which has the
axis of the torque-measuring flange as the cylinder axis, wherein its
radius given a radially outward measuring recess is smaller than that of
the peripheral cylinder jacket surface of the measuring range. Especially
possible as a variant is an imagined cylinder with an axis lying parallel
to the axis of the torque-measuring flange, but between its axis and its
outer peripheral jacket surface.

[0018]A highly precise conversion between the measured expansion and/or
stress conditions on a partially cylindrical surface on the recess floor
or on a recess wall can be performed to derive the torque applied to the
torque-measuring flange.

[0019]It is understood that a partially cylindrical recess floor can also
be present given a radially inward measuring recess.

[0020]In addition to an essentially partially cylindrical recess floor, it
is proposed that at least one measuring recess exhibit a recess floor
that deviates from a cylinder form, in particular a flat recess floor. It
is understood that a very precise conversion between expansion and/or
stress and the applied torque to be measured is also possible on a flat
recess floor. In addition, the measuring strips are easy to permanently
secure to a plane.

[0021]It is understood that a measuring recess can deviate to nearly
whatever depth from the outer or inner peripheral of the cylindrical
measuring range. It is proposed that at least one measuring recess
exhibit a recess floor with a surface corresponding to the surface of the
cylindrical measuring range toward which the measuring recess is
oriented. In other words, a recess is designed with such a depth that the
radial thickness of the cylinder in the measuring range is almost
completely traversed by the measuring recess, so that a radially outward
measuring recess runs nearly to the inner cylinder surface of the
measuring range, or that a radially inward measuring recess runs nearly
to the outer cylinder jacket of the measuring range. However, the recess
is not or at least not completely embodied as a penetration area between
the inward and outward cylinder jacket surface, but remains a thin
diaphragm. This diaphragm is both the recess floor of the measuring
recess when viewed from the one radial side and the cylinder jacket
shaped surface of the measuring range, specifically radially inward or
radially outward, when viewed from the other radial direction.

[0022]A reduction in the measuring diaphragm, meaning the remaining
material below the recess floor of a measuring recess, to a rather thin
surface results in an enhanced reproduction of an applied torque, since
the expansion and stress are strengthened. This enables a highly resolved
measurement of torque.

[0023]It is preferred that at least one measuring recess exhibit a round
cross section.

[0024]To this end, let the following terminological explanation be
provided: A "round" cross second is understood in particular as a
circular cross section. However, an expanded consideration also makes it
possible to interpret "round" as being any other cross section free of
corners, and preferably also free of straight lines. The "cross section"
of the measuring recess is viewed in particular in a cutting plane, which
lies perpendicular to the longitudinal axis of the torque-measuring
flange. The word "cross section" can be expanded to include the winding
of an interface on an imagined cylinder jacket surface around the
longitudinal axis of the torque-measuring flange. Also possible is a
cutting plane lying parallel to the longitudinal axis of the
torque-measuring flange.

[0025]Imagined in particular is a borehole with a circular cross section
given a section parallel to the longitudinal axis of the torque-measuring
flange, wherein the borehole forms the measuring recess, preferably with
a borehole axis directed radially to the longitudinal axis of the
torque-measuring flange.

[0026]Also advantageously possible from a cumulative standpoint is for at
least one measuring recess to exhibit a rectangular cross-section with
rounded corners, in particular a square cross section with rounded
corners.

[0027]Both a measuring recess with a round cross section and a measuring
recess with a rectangular, even square, cross section with rounded
corners can be relatively easily incorporated into the measuring range,
and results in relatively well known force redistributions during
exposure to a torque to be measured.

[0028]It is proposed that each measuring recess provide a measured value
transducer. It is viewed as advantageous at the very least for each
measuring recess to exhibit a varying form per measured value transducer.

[0029]The provision of several measured value transducers, e.g., expansion
measuring strips, makes it possible to verify measured values, for
example, or the different measured values can be averaged. It is also
conceivable that the different measured value transducers can measure
specific torque ranges with varying resolution levels, precisely when two
identical or different measured value transducers are arranged in
varyingly designed and/or embodied measuring recesses.

[0030]As was already explained, at least one measuring recess can open
radially inward. In such a measuring recess, the recess floor lies
radially outward, so that the measured value transducers can preferably
be arranged there.

[0031]It is proposed that the cross section of at least one measuring
recess change starting from the recess floor, preferably expand or
narrow.

[0032]In a second aspect of the invention, the object is achieved by means
of a torque-measuring flange with a measuring range situated around a
rotational axis, which incorporates measuring diaphragms, and with
measured value transducers, which measure stresses and/or deformations of
the measuring diaphragms, wherein at least two measuring diaphragms are
differently shaped and/or embodied.

[0033]As already explained from a terminological standpoint, "measuring
diaphragms" are flat segments thinner in design by comparison to the
remaining cylindrical area. Torques applied to the torque-measuring
flange can be amplified and measured on these thin flat segments and/or
around these thin flat segments, so that very precise results can be
obtained.

[0034]It is proposed that at least two measuring diaphragms exhibit a
different thickness.

[0035]The "thickness" of a measuring diaphragm is regarded as the radial
thickness. The latter is often also referred to as "material thickness".

[0036]Already the varying material thickness of the membranes makes it
possible to achieve readily distinguishable measuring ranges on the
torque-measuring flange.

[0037]Alternatively and cumulatively to a differing thickness of second
measuring diaphragms, it is proposed that at least two measuring
diaphragms exhibit a different shape. The latter can be produced both
during a projection of the measuring diaphragm on a cylindrical surface
around a measuring flange axis, or during a projection of the measuring
diaphragm on a plane parallel to the measuring flange axis. This also
makes it possible to achieve readily distinguishable expansion and/or
stress behavior with a torque applied.

[0038]Identical measuring diaphragms are preferably arranged symmetrically
relative to the rotational axis of the torque-measuring flange, in
particular rotationally symmetrical. In such a configuration, the
identically designed and symmetrically distributed measuring diaphragms
can easily be used to verify the measured values of individual measured
value transducers.

[0039]At least one measuring diaphragm can be partially cylindrical in
design. In terms of the definition of a "partially cylindrical measuring
diaphragm", reference is made to the above explanations concerning a
"partially cylindrical recess floor" of a measuring recess. Given a
suitable configuration, the recess floor of a measuring recess is
identical with the measuring diaphragm. Therefore, overall reference is
made to the analogous description for a partially cylindrical recess
floor with regard to a partially cylindrical measuring diaphragm.

[0040]Alternatively and cumulatively to a partial cylindrical measuring
diaphragm, it is proposed that at least one measuring diaphragm deviate
from a cylindrical shape, and preferably be flat. With respect to the
geometric definition, let reference be made to the above explanations
regarding a corresponding recess floor in this conjunction. Measured
value transducers such as expansion measuring strips are especially
simple to secure on a flat measuring diaphragm.

[0041]It is proposed that at least one measuring diaphragm exhibit an
essentially constant thickness. In a measuring diaphragm embodied in this
way, there are no extremely precise requirements as to where exactly on
the measuring diaphragm a measured value transducer like an
expansion-measuring strip must be affixed. This can make it easier to
compare the values of different measured value transducers to each other.

[0042]At least one measuring diaphragm preferably has a circular shape.

[0043]With respect to terminology, let it be explained that a "circular
shape" around the measuring flange axis can result in particular given a
projection onto a plane parallel to the axis of torque-measuring flange
or a radial projection onto a cylinder jacket-shaped projection surface.
Precisely a measuring diaphragm that is circular relative to a can be
easily incorporated into the measuring range through a borehole.

[0044]Let it be noted that the measuring diaphragm need not be "circular"
in the exact mathematical sense of the word to realize this feature. It
is also not necessary for the diaphragm to reflect the mathematical
definition in the best possible physical approximation. Rather, it is
already sufficient if at least essentially a circular shape exists, for
example of the kind achieved when incorporating a conventional borehole
into a metal work piece. In particular, a radius for a borehole diameter
can fluctuate around the median value by about 10% and still be regarded
as circular.

[0045]It is understood that, given numerous possible embodiments, it is
difficult to define a border for the measuring diaphragm relative to a
recess wall. If the wall passes over into the measuring diaphragm as an
edge, the edge can be regarded as the defining border of the measuring
diaphragm. In another aspect, a surface that remains uniform over a
certain area in terms of curvature and thickness can be interpreted as
the measuring diaphragm.

[0046]It is proposed that at least one measuring diaphragm be rectangular,
in particular square, and preferably embodied with rounded corners. Such
a form can also be produced relatively quickly.

[0047]A measured value transducer is preferably provided for each
measuring diaphragm. A measured value transducer can advantageously be
provided at each differently embodied or configured measuring diaphragm.
Both facilitate the comparability, and hence the measuring accuracy, of
the individual measured values at the torque-measuring flange.

[0048]At least one measuring diaphragm can be situated radially outward on
the measuring range. A radially outward measuring diaphragm is able to
absorb an applied torque with only a relatively slight force, since the
measuring diaphragm has a greater lever radially outward relative to the
axis of the torque-measuring flange.

[0049]In this way, a precise measurement can also take place for higher
torques, or the diaphragm can be given a very thin design.

[0050]Possible measured value transducers include in particular expansion
measuring strips and/or magnetic measured value transducers. Expansion
measuring strips were referred to above in several examples. It is
understood that these can be respectively replaced completely or in part
by magnetic measured value transducers or other suitable measuring
devices.

[0051]It is advantageous if at least one measured value transducer lying
radially inward be arranged at the measuring area, in particular so as to
be able to measure smaller torques well. Alternatively and cumulatively,
it can be advantageous for at least one measured value transducer to be
situated radially outward on the measuring range, in particular for
measuring larger torques. A combination of radially inward and radially
outward measured value transducers can be used very suitably for
precisely acquiring torques in various ranges of magnitude.

[0052]It is understood that the measuring diaphragms or measuring recesses
as well as the radially inward measuring recesses or radially outward
measuring diaphragms can also be configured independently of the
remaining features of the present invention in a manner advantageous for
a torque-measuring flange.

[0053]The invention will be described in greater detail below based on an
exemplary embodiment, drawing reference to the drawing. Shown on:

[0054]FIG. 1 is a diagrammatic depiction of a perspective view of a
section measuring roughly two thirds of a torque-measuring flange with
varyingly deep measuring recesses or varyingly thick measuring membranes,
as well as

[0055]FIG. 2 is a diagrammatic section through a complete torque-measuring
flange as embodied on FIG. 1, with a cutting plane at half the axial
height of the torque-measuring flange from FIG. 1.

[0056]The torque-measuring flange 1 in the figures essentially consists of
a pair of connecting flanges 2, 3, which are configures as annularly
circular disks, and provided with boreholes 4 (exemplarily designated).
Shafts or other parts of a machine or some other device are linked to the
connecting flange 2, 3 via coupling boreholes 4, e.g., a torque-guiding
shaft of a measuring bench.

[0057]The two connecting flanges 2, 3 of the torque-measuring flange 1 are
designed as a single piece with a measuring range 5, wherein an
essentially cylinder jacket shaped wall 6 of the torque-measuring flange
11 is designed as the "measuring range" 5.

[0058]If a torque around a rotational axis 7 of the torque-measuring
flange 1 is applied to the connecting flange 2, 3 during operation of the
torque-measuring flange, it is also applied in the measuring range 5, so
that expansions and stresses arise in the cylindrical wall 6 of the
measuring range 5, which permit conclusions as to the magnitude of the
applied torque.

[0059]To be able to acquire these values, the torque-measuring flange 1 is
equipped with a plurality of expansion-measuring strips 8 (exemplarily
designated), which are all applied radially inward to a radially inward
cylinder jacket-shaped surface 9 of the measuring range 5 or its cylinder
wall 6. Specifically, eight expansion strips 8 are provided, namely
distributed symmetrically around the rotational axis 7 of the
torque-measuring flange 1.

[0060]Eight recesses are incorporated into the wall 6 of the measuring
range 5 at a radially outward sheathing cylinder jacket surface 10, which
lies coaxially with the inner surface 9, wherein four are flat recesses
(exemplarily designated 11) and four are deep recesses (exemplarily
designated 12).

[0061]The flat recesses 11 alternate with the deep recesses 12 in the
outer surface 10 of the wall 6 of the measuring range 5, and each
family--i.e., that of the flat recesses 11 or that of the deep recesses
12--is arranged in a rotationally symmetrical manner around the axes 7 of
the torque-measuring flange 1.

[0064]The expansion measuring strips 8 are secured to the radial interior
side of the measuring diaphragms 18, 19, radially concentric with each
recess 11, 12. The expansion measuring strips are longer than the
recesses 11, 12 in their axial extension. By contrast, the floor surfaces
16 of the recesses 11, 12 are wider than the expansion measuring strips 8
with respect to the tangential extension around the axis 7 of the
torque-measuring flange 1.

[0065]The recesses 11, 12 in the measuring range 5 amplify deformations or
stresses owing to an applied torque, so that measured value transducers 8
provided in the measuring range 5 can perform significantly more
sensitive measurements. In this case, the recess floors 16, 17 or
measuring diaphragms 18, 19 form locations that are correspondingly
subjected to a greater stress or deformation.

[0066]The differing depths and varying areas between the flat measuring
recesses 11 and the deep measuring recesses 12 give rise to areas in the
measuring range 5 that react to different extents to the application of
the torque, so that the torque-measuring flange 1 can exhibit several
sensitivity ranges.

[0067]The advantage to the measuring diaphragms 18, 19 is that the
measured value transducers 8 can essentially perform shear measurements,
which can be conducted relatively precisely.

[0068]In particular, the cross section of a recess 11, 12 can be measured
perpendicular to a recess depth to lie along an exemplarily designated
central recess axis 20. In the case of radially oriented recesses in
cylindrical measuring ranges, the cross section is preferably viewed on
cylindrical surfaces situated around the rotational axis 7, or on a
cutting plane parallel to the rotational axis 7. In the latter two cases,
the depth is measured radially.

[0069]In this conjunction, the term "thickness of a measuring diaphragm"
denotes the thickness of a measuring diaphragm, wherein the form of the
measuring diaphragms is determined by its edges.

[0070]The exemplary embodiment does not show radially outward measuring
diaphragms or radially inwardly opening measuring recesses, which can
additionally increase the measuring accuracy for torque-measuring
flanges, since larger deflections are encountered radially outward.

[0071]The reaction of the measuring diaphragms 18, 19 or measuring range 5
to an applied torque can be influenced by changing the cross sections of
the recesses as a function of the depth 20 in the recess 11, 12. The
recesses 11, 12 can expand or narrow in particular relative to the recess
floor 16, 17, or exhibit walls 13, 14 that are not oriented or situated
radially to the rotational axis and/or perpendicular oriented to the
radius around the rotational axis and/or parallel to the rotational axis.
Given a suitable selection of the cross sectional change, the stress
signal and/or deformation of measuring diaphragms 18, 19, the recess
floor 16 17 or other assemblies of the measuring range 5 can be enhanced,
thereby making it possible to increase the sensitivity of the mechanical
device, and hence the entire torque-measuring flange 1.

[0072]As directly evident, the measuring diaphragm in this exemplary
embodiment exhibits a thickness that varies over its surface. This can be
minimized in alternative exemplary embodiments by adjusting the floor of
the measuring recesses to the opposing surface of the measuring range. In
like manner, the opposing surface of the measuring range can also be
correspondingly machined and adjusted to the floor of the respective
measuring recess. In this way, the measuring diaphragms can essentially
be given a flat, shell or cylindrical form, for example.